OsmoMSC permits ESME configuration with password length > 8

The SMPP 3.4 specification defines the password field as a "Variable-length octet string with maximum length of 9", and according to table 3-1 this means including the terminating NUL-byte.

However, OsmoMSC allows to configure longer passwords in the ESME configuration. Those passwords will then never match, as libsmpp34 performs length validation and generates a parser error for anyone trying to send a longer password via SMPP.